In the related art, there is a known gripping mechanism with which an object such as living tissue is gripped by using a pair of gripping pieces that are joined in a pivotable manner, wherein a toggling mechanism is utilized (for example, see Japanese Unexamined Patent Application, Publication No. 2007-301692). The toggling mechanism is provided with a pair of linkages that are joined so as to be pivotable about a pivoting axis shared with the pair of gripping pieces, and an opening motion of the pair of linkages is converted to a closing motion of the pair of gripping pieces. In this structure, it is possible to increase the gripping force exerted by the pair of gripping pieces in accordance with the lengths of the pair of linkages.